diff --git a/CHANGES.md b/CHANGES.md
index 4d65d94a..a79be2c3 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -16,6 +16,8 @@
   context. This variable contains a comment block that signals that
   the file content is generated by batou. (#356)
 - Development: update Sphinx to 5.3.0 to fix readthedocs build failures.
+- Component object model: Class variable .instances renamed to ._instances
+  to avoid collisions with user-applications.
 
 ## 2.5.0b3 (2024-08-05)
 -----------------------